Points system conveyor

ABSTRACT

A conveyor points system using an endless loop deformable stringer has a cantilever outrigger which is resiliently flexible in one plane only and defines, when flexed, a curved path for one run of the stringer. Control of the degree of flexing enables the cantilever, and thus the conveyor path defined by the one run of the stringer, to be selectively registered with different conveying paths. The conveyor thus enables a points system to be utilized which is capable of providing a number of curved routes through the points without steps or sharp bends.

Q United States Patent [1 1 [111 3,844,403 Stauber 1 Oct. 29, 1974POINTS SYSTEM CONVEYOR 2,909,267 10/1959 Ferguson, Jr 198/31 ACInventor: HansJJlrich Stauber, Grut 3,707,218 12/1972 Payne 198/109Switz rlan Primary Examiner-Richard A. Schacher ['73] Assignee: FeragAG, Hinwil, Switzerland Asslsmm Examwr*Rlchard Thomson Attorney, Agent,or Firm-Werner W. Kleeman [22] Filed: Nov. 5, 1973 [21] Appl. No.:413,169 [57] ABSTRACT A conveyor points system using an endless loop de-[30] Foreign Application priority Data forrr able sttlrinier acalmtilevelr outrigger whiclli1 is rest ten y ext e in one p ane on y ane mes, w en I972 swltzcrlaqqlllillllY'Figm' flexed, a curved path forone run of the stringer. Con- [52] US. Cl. 198/109, 198/95 trol of thedegree of flexing enables the cantilever, and [51] Int. Cl. 1E6Sg 41/00thus the conveyor path defined by the one run of the [58] Field ofSearch 198/109, 31 R, 31 AC, 81, stringer, to be selectively registeredwith different con- 198/93, 95, 124, 125, 182; 267/ 160 veying paths.The conveyor thus enables a points system to be utilized which iscapable of providing a [56] References Cited number of curved routesthrough the points without UNITED STATES PATENTS Steps or Sharp bends-2,880,847 4/1959 Kelley 198/109 10 Claims, 8 Drawing Figures it I 56 l13 51g 65 I l I 71 V 79 0 1, 55 i v 77 6 50 W 62 W R-' i2 f a I '52 r 58I 68 76 78 12 L56 11 l 48 51 75 8 55 r9 as V 5 1 t 30 51$ PATENTED OCT29 I974 SHEET 20F 4 SHEEF 30? 4 PATENTEDUN 29 1914 POINTS SYSTEMCONVEYOR FIELD OF THE INVENTION BACKGROUND TO THE INVENTION When a feedpath is provided by circulating chain conveyors and it is necessary tointroduce a change in the feed path by means of a points system, thechange is normally effected by changing the height of one conveyor atthe points so that it effectively changes the feed path which is thencontinued by way of a second conveyor defining a new path. If, forexample, the conveyor is a load-bearing conveyor provided by the upperruns of serially aligned chains, one of the upper runs of the points maybe lowered beneath the level of the upper run of a second conveyor sothat the loads descend a small step and are carried forward by thesecond conveyor to the new path. The old path may be restored by raisingthe run of the lowered conveyor again. If the conveyor is an overheadconveyor rather than a load-bearing conveyor, then the conveyor run nolonger required at the points is normally lifted out of the path whichis then continued by a second conveyor which may be lowered into itsplace.

DISADVANTAGES OF THE PRIOR ART Whatever the system used, it will beappreciated that a points system in accordance with the prior artnormally involves shifting conveyors bodily with respect to one anotherand having a separate conveyor for defining each route through thepoints system. This is cumbersome and costly.

OBJECT OF THE INVENTION An object of this invention is the provision ofa conveyor able to provide more than one route through a conveyorsystem.

THE INVENTION In accordance with the present invention there is provideda conveyor comprising a cantilever outrigger supported at one end andresiliently flexible in one plane while being inflexible andsubstantially immovable in two other planes perpendicular to said oneplane, a flexible guide extending along the outrigger in said one plane,return devices at opposite ends of the conveyor, an endless deformablestringer looped around the return devices and having one run constrainedby the guide to follow the contour of the outrigger in said one plane, amechanism connected to drive the stringer, and an actuator operable todisplace the unsupported end of the outrigger laterally in said oneplane to any one of different predetermined positions by resilientlyflexing the outrigger whereby said one run of the con veyor isdeformable along a curved path to bring its end into alignment with aselected one of branch paths which extend away from said predeterminedpositions respectively.

ADVANTAGES OF THE INVENTION By using the invention a single chainconveyor can be used to provide two or more routes, individuallyselectable, through the points system and each of the routes can be madewithout bodily movement of the conveyor and is free of steps at its endwhile able to provide a smooth change in direction for articlesconveyed.

PREFERRED FEATURES OF THE INVENTION Preferably the outrigger comprises aleaf spring lying in a vertical plane and having a guide extending alongone horizontal edge.

Suitably the guide includes a flexible rail attached to the upperhorizontal edge of the leaf spring.

The invention will now be described in more detail, by way of examples,with reference to the accompanying drawings, in which:

IN THE DRAWINGS FIGS. I to 3 are diagrammatic perspective views of threedifferent embodiments of outrigger used to explain the principle of theinvention;

FIG. 4 is a simplified side view of points apparatus adapted to operatein accordance with the principle of FIG. 2;

FIG. 5 is a section along the line 55 of FIG. 4;

FIG. 6 is a section along the line 66 of FIG. 5;

FIG. 7 is a section along the line 7-7 of FIG. 6;

FIG. 8 is a section along the line 8-8 of FIG. 5.

Although the drawings do not show a complete conveyor system having asingle branch or feed path coming to the points and, a number of feedpaths, individually selectable, branching away from the points, such abasic layout is so well known it is believed to be quite unnecessary todescribe or illustrate it in detail. However, for the convenience of thereader the diflerent embodiments to be described are for connecting asingle main branch, leading to the points, selectively to one of threefeed branches diverging away from the points. The conveyor paths all liein the horizontal plane and are assumed to be of load-bearingconstruction in which the conveyor has an upper travelling run whichstands just proud of a smooth slide-way provided by static horizontalsurfaces extending along each side of the run.

DIFFERENT EMBODIMENTS OF THE INVENTION In FIGS. 1 to 3 which show inbroad outline three ways of putting the invention into effect to explainits principle, corresponding parts of the embodiments bear the samereferences.

Referring to FIG. I, the dash-dot. line E indicates the direction of aninlet. conveyor section to a points system and the dash-dot lines A,, Aand A indicate the direction of three exit sections to the points systemand to which the inlet section can be switched by a flexible conveyor.The flexible conveyor is provided with resiliently bendable outrigger 10having a leaf spring 12 clamped in cantilever manner at position 13 andsupporting a flexible rail section II on its upper edge. The free end ofthe leaf spring I2 on the right in FIG. 1 is held by a clevis 14 mountedon a shank 15. The shank 15 is anchored at one end of a radius rod 16the other end of which is hinged to a pintle 17 which extends through aslot 18 formed in the radius rod 16.

The pintle 17 is mounted on a block 19. Means which are not shown enablethe block 19 to slide and to be locked in a selected position in thedirection of the arrow 27 and with respect to a further block 26. Asecond pintle 25 is mounted on the block 26 and a collar 24 of a furtherradius rod 20 is pivotably supported on the second pintle, the other endof the radius rod 20 being provided with a lug having a bore in whichthe shank I5 is pivotally supported. An operating rod 22, which isreciprocatingly slidable in the direction of the arrow 23, is pivotallyconnected to the lug.

It should be noted that the length of the leaf spring 12 between theclamping positions 13 and the clevis 14 is longer than the length of thesecond radius rod 20, and the length of the second radius rod is longerthan the length of the radius rod 16 between the shank l5 and theposition at which the pintle 17 engages. The outrigger is resilientlydeflected if the operating rod 22 is moved in the direction of the arrow23 for example to the right, from the position illustrated in FIG. 1.During the deflecting motion the free end of the outrigger 10 describesa circular arc U which extends around the axis of the pintle 25. Theclevis I4 and therefore the free end of the leaf spring 12 does notmerely perform a pivoting motion around the axis of the joint pintle 25in the course of the aforementioned deflecting motion but -because ofthe shorter radius rod 16 also describes a pivoting motion around theaxis of the pintle 17 which pivoting motion in superimposed on the firstpivoting motion. The operating rod 22 therefore effectively applies atorque to the free end of the outrigger 10 so that the deflectedoutrigger 10 follows approximately the course V which is shown in brokenlines and which in turn is substantially a good approximation to acircular arc but not to a parabola. For any practical deflection theoutrigger 10 will therefore define a guide path which is practically inthe form of a circular arc.

Any shortening or lengthening of the effective length of the radius rod16 in this embodiment also enables the direction of the tangent at theend of the course V to be altered, that is to say the radius ofcurvature of the guide path in the form of a circular arc can be alteredwithin specific limits. Although the length of the arc changes in thecourse of such changes of the curvature radii of the guide path, thestarting positions of the exit sections A, A are well defined. As theleaf spring 12 is still clamped at one end so as to be resistant tobending, as will be described subsequently, provision is preferably madeto permit it a limited guided longitudinal displacement as is describedlater.

FIG. 2 shows an embodiment which is somewhat simplified in relation tothe embodiment illustrated in FIG. 1. It discloses an outrigger 10,clamped firmly at 13 and having a leaf spring 12 and a rail section 11,the outrigger 10 being retained at its free end by a clevis 14. A shank15 of the clevis 14 is mounted on a radius rod 16 which is hinged to apintle 17 but is not slidable with respect thereto as was the case inthe FIG. 1 embodiment. The pintle 17 is fixed to a block 19 which isassumed to be stationary. An operating rod 22 which is reciprocatable inthe direction of the arrow 23 acts on the radius rod 16 at a pivot 21.It follows that the embodiment of FIG. 2 differs from that of FIG. I bythe omission of the radius rod which defines the sliding path U of thefree end of the outrigger 10. Moving the operating rod 22 axially in theembodiment of FIG. 2 again causes a torque to be applied to the free endof the outrigger 10 because the length of the radius rod in this case isalso shorter than the length of the leaf spring 12 between the clampingposition 13 and the clevis 14. Accordingly, the outrigger 10 in thisembodiment will substantially follow the shape of a circular arc V whenthe outrigger is deflected while the path traversed by the free ends ofthe outrigger 10 is once again a circular are U. However, the directionof the end tangent with respect to the lines V cannot be altered in thisembodiment.

The embodiment illustrated in FIG. 3 is still further simplified withrespect to the previously described embodiments. An outrigger 10 isprovided with a tapering leaf spring 12 which is clamped firmly at oneend at 13 and which carries along its upper edge a rail section 11. Thefree end of the leaf spring 12 is attached to a clevis with a shank 28on which a push rod is pivoted by means of a collar 29. As the leafspring 12 diminishes from the clamping position 13 towards its free endit tends to be deflected practically in a circular arc, as indicated bythe broken line V, if the push rod 22 is displaced axially, andconsequently a force but not a torque is applied to the free end of theleaf spring 12.

PREFERRED EMBODIMENT OF THE INVENTION Turning now to the embodimentshown in FIGS. 4 and 5 what is here shown is simply the switchingconveyor of a points system. In FIG. 5 it is to be assumed that theinlet section or branch to the points system terminates on the right ofFIG. 5 and the exit sections or branchesup to three in the presentexample extend from the left-hand side of FIG. 5. The switching conveyor90 is provided with a base plate 30 which supports two halves 32, 33 ofa sliding table by means of four columns 31, a flared gap in which isdefined by the dash dot lines V, V" between the two table halves. Asolid support column 34, the upper end of which supports a guide andbearing block 35, is also mounted on the base plate 30. As may be seenby reference to FIGS. 5 to 7 one side of the block 35 is provided with arecess 36 which is laterally defined by lugs 37, 38. The upper zone ofthe recess is bridged by a bolt 39, which is mounted in the lugs 37, 38and on which a bifurcated rocker lever 40 is pivotally supported bymeans of bushes. As shown in FIG. 6 a trunnion 41 is pivotably supportedby means of bearing bushes on the free bifurcated end, and, twoprojecting members 42, 43 of two L-shaped clamping pieces 44, 45 areclamped by clamping screws 46 to the trunnion. FIG. 7 shows that one endof the upright leaf spring 12 of the outrigger is clamped firmly betweenthe two clamping pieces 44 and 45. Accordingly, the leaf spring 12 isresistant to bending with respect to the block 35 but because of thepivoting suspension provided by the parts, 39 to 45 it is able to moveaxially in its own plane a small amount.

A low-friction rail section 11, in the present case in the form of aninverted U, is mounted along the upper edge of the leaf spring 12. Thepath of the rail section 11 is continued on the block 35 by means of aplastics strip 47 let into the top surface of the block and extendingrectilinearly and having a top face which is coplanar with the top faceof the rail section 11.

On the side which appears on the right in FIG. 5 the block 35 isprovided with a further recess 48, defined by lateral lugs 49, 50 andbridged by a drive shaft 511 which is rotatably supported in the lugs49, 54). A first chain sprocket wheel 52 is keyed to the drive shaft 51between the lugs 49, 50 and a further chain sprocket wheel 53 is keyedon one end of the shaft 51 which extends laterally beyond the lug 50.The chain sprocket wheel 52 is coupled by a chain 54 to an output pinion55 of a driving unit 56, for example a geared motor, which is mounted onthe base plate 30. The chain sprocket wheel 52 meshes with a rollerchain 57 whose upper run or stringer paid off from the chain sprocketwheel 52 travels first along the plastics strip 47 and then along therail section it to a tensioning and reversing roller 58 which isdisposed at the free end of the leaf spring 12.

As may be seen by reference to FIG. 5 two slotted bearing extensions 61,62 are provided for the reversing roller 56 and two downwardlyprojecting extensions 63, 64 are bolted to the sides of the free end ofthe leaf spring 12, which appears in the left hand side, with theinterposition of two intermediate members 59, 60. The

function of the extensions 63, 64 corresponds to that of the clevis 14of FIG. 2 for which purpose their lower ends are connected to one end ofa radius rod 67 (FIG. 4) which corresponds to the radius rod 16 of FIG.2. As shown in FIG. 4, the other end of the radius rod 67 is pivotablysupported on a vertical trunnion 68 which is mounted on the base plate36. The ends of the bearing extensions 61, 64 that project form the freeend of the leaf spring 12 have horizontal aligned slots for thereception in longitudinally slidable manner of the nonrotatable shaft 68of the reversing pulley 55. The position of the reversing pulley 58 maybe adjusted lengthwise of the leaf spring 12 by turning control screws69 thus enabling the roller chain 57 providing the stringer to betensioned. It will be understood that a tensioning spring, not shown inthis arrangement, acts on the shaft 68 and tends to thrust the reversingpulley 58 into its outermost position in order to retain the rollerchain 57 in the tensioned state. The extension 64 also has an anglepiece 70 mounted upon it on which the piston rod 2 of a double actinghydraulic unit 73 is hinged at position I, the hydraulic unit in turnbeing hinged on a stationary part of the machine frame at position 74.

FIG. 8 shows that upper parts of the links of the roller chain 57 areextended horizontally away to the sides of the chain run and support atrack plate 75 which in turn is constructed in inverted C-shape to spanthe roller chain 57. To ensure that the track plates 75 are properlyguided, as may be seen by reference to FIGS. 4, 7 and 8, spaced lateralguide plates 76, 77 are bolted at regular intervals to the leaf spring12 along its length. Bolts 80 and nuts 8] are used for this purpose andthe upper and lower edges of the guide plates are in alignment with eachother and are so cross-sectioned, that as shown in FIG. 8, the sideinwardly turned edges of the track plates 75 are guided horizontally andvertically. The distance between successive side plates 76 or 77 is soselected that they do not obstruct the intended flexure of the leafspring I2.

OPERATION OF THE PREFERRED EMBODIMENT If the piston rod 72 is moved tothe top or bottom (FIG. 5) when the hydraulic unit 73 ispressure-biased, the free end of the leaf spring 12 is deflected inaccordance with the displacement of the piston rod. Deflection isaccompanied not only by the action of the force which is applied by thehydraulic unit but is also subject to a torque approximately of themagnitude of the force of the hydraulic unit multiplied by the effectivelength of the radius rod 67. Accordingly, the leaf spring I2 will bedeformed in good approximation to a circular arc and not to a parabola.It should be noted that the purpose of the radius rod 67 is not only toenable the force applied by the hydraulic unit 73 to act as torque onthe free end of the leaf spring but also to support the free end of theleaf spring and the parts mounted thereon so that the load of theseparts need not be supported by the clamping pieces 45.

When the leaf spring I2 is deflected the upper and lower ends of theside plates 77 and 76 respectively define a polygonal line whichapproximately corresponds to an arcuate line described approximately byan arc which extends parallel to the arc described by the leaf spring112 and the rail section ll. If the inlet branch or section and the exitbranch or sections are imagined as track chains which extend in arcuateor rectilinear form it will be appreciated that goods conveyed by theconveying stringers of serially disposed conveyors are moved withoutjerks and over a kinkfree conveying path from the inlet section via thepoints system provided by the switching conveyor to the connected exitsection. In FIG. 6 a conveyed article composed of a stack of papersheets is diagrammatically illustrated by the pick and dot outline Z andit will be seen that it straddles the conveyor in the manner of an archand the marginal underside of the stack rest and slide along halves 52,33 of the sliding table, while the central underside of the stack restson and is carried along the conveyor upper run.

In the preceding description it was assumed that the conveying stringerof the track chain comprising the roller chain 57 and the track platespasses from the clamping position of the leaf spring I2 towards the freeend thereof but it will be understood that the circulating direction ofthe said track chain can also be reversed. In other words, the railpoints can be used as distribution points and as collecting points inthe application of the rail points described hereinabove.

A further advantage of the system described herein is that it can beclosely adapted on. site to existing inlet and exit sections, forexample by a simple limitation of the length of stroke of the hydraulicunit 73.

I claim:

1. A conveyor comprising a cantilever outrigger supported at one end andresiliently flexible in one plane while being inflexible andsubstantially immovable in two other planes perpendicular to said oneplane, a flexible guide extending along the outrigger in said one plane,return devices at opposite ends of the conveyor, an endless defomiablestringer looped around the return devices and having one run constrainedby the guide to follow the contour of the outrigger in said one plane, amechanism connected to drive the stringer, and an actuator operable todisplace the unsupported end of the outrigger laterally in said oneplane to any one of different predetermined positions by resilientlyflexing the outrigger whereby said one run of the conveyor is deformablealong a curved path to bring its end into alignment with a selected oneof branch paths which extend away from said predetermined positionsrespectively.

2. A conveyor as claimed in claim 1, in which the outrigger comprises aleaf spring lying in a vertical plane and having the guide extendingalong one horizontal edge.

3. A conveyor as claimed in claim 2, in which the guide includes aflexible rail attached to the upper horizontal edge of the leaf spring.

4. A conveyor as claimed in claim 3, in which the cross-setion of theleaf spring tapers progressively towards its free end.

5. A conveyor comprising a cantilevered outrigger, a stand supportingone end of said outrigger, a leaf spring lying in a vertical plane andextending the length of said outrigger, said leaf spring having auniform crosssection and being resiliently flexible in the horizontalplane while being inflexible and substantially immovable in the verticalplane, a flexible guide rail extending along hte top edge of said leafspring in the horizontal plane, return rollers at opposite ends of theconveyor one being attached to the free end of said leaf spring and theother attached to said stand, an inextendible deformable stringer loopedaround said rollers and having one run constrained by said rail and sideguides to follow the contour of the upper edge of said leaf spring,spaced attachments connecting said side guides to said leaf spring, amotorized drive unit on said stand and operatively connected to drivesaid stringer, a reciprocatable actuator connected to the free end ofsaid outrigger and operable to displace said free end horizontally todifferent predetermined positions, such displacement being accompaniedby flexing of the leaf spring so that the guide rail and conveying runof the stringer follows a curved path.

6. A conveyor as claimed in claim 5, in which said stringer carriesconveyor plates having marginal edges lying at a level beneath thecentral positions of said conveyor plates, and said side guides arespaced along the length of the leaf spring to provide slideways alongwhich opposite marginal edges of the conveyor plates travel duringoperation of the conveyor.

7. A conveyor as claimed in claim 5, in which the free end of the leafspring carries stringer tensioning means operable to displace therotational axis of one roller lengthwise of the leaf spring.

8. A conveyor as claimed in claim 5, including a radius rod extendinghorizontally beneath the leaf spring between two upright pivotal axesone of which is fixed relative to said free end and the other of whichis fixed relative to said stand.

9. A conveyor as claimed in claim 5, including a suspension supportmechanism attaching the fixed end of the leaf spring to said stand, saidmechanism including pivoted links interconnected whereby twisting andsignificant vertical movement of said fixed end is effectively preventedbut limited horizontal movement of said fixed end is allowed.

10. A conveyor as claimed in claim 5, including two parallel radius rodsof different lengths lying in the plane of the leaf spring and parallelthereto, each being pivoted at one end to the free end of the leafspring and the longer radius rod having a fixed upright pivot at itsother end while the shorter radius rod at its other end has an uprightpin and slot connection to a pivoted axis which is displaceablelengthwise of the leaf spring, the actuator being pivotally connected tothe free end of the leaf spring and applying a lateral deflecting torqueto it to change the contour of the leaf spring.

1. A conveyor comprising a cantilever outrigger supported at one end andresiliently flexible in one plane while being inflexible andsubstantially immovable in two other planes perpendicular to said oneplane, a flexible guide extending along the outrigger in said one plane,return devices at opposite ends of the conveyor, an endless deformablestringer looped around the return devices and having one run constrainedby the guide to follow the contour of the outrigger in said one plane, amechanism connected to drive the stringer, and an actuator operable todisplace the unsupported end of the outrigger laterally in said oneplane to any one of different predetermined positions by resilientlyflexing the outrigger whereby said one run of the conveyor is deformablealong a curved path to bring its end into alignment with a selected oneof branch paths which extend away from said predetermined positionsrespectively.
 2. A conveyor as claimed in claim 1, in which theoutrigger comprises a leaf spring lying in a vertical plane and havingthe guide extending along one horizontal edge.
 3. A conveyor as claimedin claim 2, in which the guide includes a flexible rail attached to theupper horizontal edge of the leaf spring.
 4. A conveyor as claimed inclaim 3, in which the cross-setion of the leaf spring tapersprogressively towards its free end.
 5. A conveyor comprising acantilevered outrigger, a stand supporting one end of said outrigger, aleaf spring lying in a vertical plane and extending the length of saidoutrigger, said leaf spring having a uniform cross-section and beingresiliently flexible in the horizontal plane while being inflexible andsubstantially immovable in the vertical plane, a flexible guide railextending along hte top edge of said leaf spring in the horizontalplane, return rollers at opposite ends of the conveyor one beingattached to the free end of said leaf spring and the other attached tosaid stand, an inextendible deformable stringer looped around saidrollers and having one run constrained by said rail and side guides tofollow the contour of the upper edge of said leaf spring, spacedattachments connecting said side guides to said leaf spring, a motorizeddrive unit on said stand and operatively connected to drive saidstringer, a reciprocatable actuator connected to the free end of saidoutrigger and operable to displace said free end horizontally todifferent predetermined positions, such displacement being accompaniedby flexing of the leaf spring so that the guide rail and conveying runof the stringer follows a curved path.
 6. A conveyor as claimed in claim5, in which said stringer carries conveyor plates having marginal edgeslying at a level beneath the central positions of said conveyor plates,and said side guides are spaced along the length of the leaf spring toprovide slideways along which opposite marginal edges of the conveyorplates travel during operation of the conveyor.
 7. A conveyor as claimedin claim 5, in which the free end of the leaf spring carries stringertensioning means operable to displace the rotational axis of one rollerlengthwise of the leaf spring.
 8. A conveyor as claimed in claim 5,including a radius rod extending horizontally beneath the leaf springbetween two upright pivotal axes one of which is fixed relative to saidfree end and the other of which is fixed relative to said stand.
 9. Aconveyor as claimed in claim 5, including a suspension support mechanismattaching the fixed end of the leaf spring to said stand, said mechanismincluding pivoted links interconnected whereby twisting and significantvertical movement of said fixed end is effectively prevented but limitedhorizontal moVement of said fixed end is allowed.
 10. A conveyor asclaimed in claim 5, including two parallel radius rods of differentlengths lying in the plane of the leaf spring and parallel thereto, eachbeing pivoted at one end to the free end of the leaf spring and thelonger radius rod having a fixed upright pivot at its other end whilethe shorter radius rod at its other end has an upright pin and slotconnection to a pivoted axis which is displaceable lengthwise of theleaf spring, the actuator being pivotally connected to the free end ofthe leaf spring and applying a lateral deflecting torque to it to changethe contour of the leaf spring.